Flask-SocketIO: Websocket transport not available when using eventlet with the gunicorn web server

An exception is thrown during the upgrade mechanism:

12e130f2f9e3430da0b461d634f40649: Received request to upgrade to websocket
[2015-10-13 23:28:00 +0000] [5684] [ERROR] Error handling request
Traceback (most recent call last):
  File "/home/miguel/Documents/dev/flask/flask-socketio/venv27/lib/python2.7/site-packages/gunicorn/workers/async.py", line 52, in handle
    self.handle_request(listener_name, req, client, addr)
  File "/home/miguel/Documents/dev/flask/flask-socketio/venv27/lib/python2.7/site-packages/gunicorn/workers/async.py", line 105, in handle_request
    respiter = self.wsgi(environ, resp.start_response)
  File "/home/miguel/Documents/dev/flask/flask-socketio/venv27/lib/python2.7/site-packages/Flask-0.10.1-py2.7.egg/flask/app.py", line 1836, in __call__
    return self.wsgi_app(environ, start_response)
  File "/home/miguel/Documents/dev/flask/flask-socketio/venv27/lib/python2.7/site-packages/engineio/middleware.py", line 32, in __call__
    return self.engineio_app.handle_request(environ, start_response)
  File "/home/miguel/Documents/dev/flask/flask-socketio/venv27/lib/python2.7/site-packages/socketio/server.py", line 301, in handle_request
    return self.eio.handle_request(environ, start_response)
  File "/home/miguel/Documents/dev/flask/flask-socketio/venv27/lib/python2.7/site-packages/engineio/server.py", line 224, in handle_request
    environ, start_response)
  File "/home/miguel/Documents/dev/flask/flask-socketio/venv27/lib/python2.7/site-packages/engineio/socket.py", line 75, in handle_get_request
    start_response)
  File "/home/miguel/Documents/dev/flask/flask-socketio/venv27/lib/python2.7/site-packages/engineio/socket.py", line 110, in _upgrade_websocket
    return ws(environ, start_response)
  File "/home/miguel/Documents/dev/flask/flask-socketio/venv27/lib/python2.7/site-packages/eventlet-0.17.4-py2.7.egg/eventlet/websocket.py", line 113, in __call__
    ws = self._handle_hybi_request(environ)
  File "/home/miguel/Documents/dev/flask/flask-socketio/venv27/lib/python2.7/site-packages/eventlet-0.17.4-py2.7.egg/eventlet/websocket.py", line 195, in _handle_hybi_request
    sock = environ['eventlet.input'].get_socket()
KeyError: 'eventlet.input'

About this issue

Original URL
State: closed
Created 9 years ago
Comments: 18 (8 by maintainers)

Most upvoted comments

@incognick Note that you have installed eventlet in your virtualenv. Eventlet and gevent are different and incompatible. Flask-SocketIO gives you the option to use either one. If you want to use gevent, then uninstall eventlet from your virtualenv, and then install gevent and gevent-websocket.

As a side note, if you consider ever porting your app to Python 3, then eventlet is much more stable on that version than gevent, which only recently was ported.

miguelgrinberg on Nov 24, 2015